/Engine/Source/Runtime/PakFile/Public/IPlatformFilePak.h
Get a list of RelativePathFromMount for every file in the given Pak that lives in any of the given chunks. Only searches the Pruned DirectoryIndex
void GetPrunedFilenamesInChunk ( const [FString](API\Runtime\Core\Containers\FString) & InPakFilename, const [TArray](API\Runtime\Core\Containers\TArray)< int32 > & InChunkIDs, [TArray](API\Runtime\Core\Containers\TArray)< [FString](API\Runtime\Core\Containers\FString) > & OutFileList )